1. Field
The present invention generally relates to sliding drawers and, in particular, drawers having electrically controlled mechanisms that require an electrical connection to the sliding drawer.
2. Description of the Related Art
Medications that are expensive or are controlled substances are carefully controlled in hospitals and other healthcare facilities. Many facilities use Automated Dispensing Machines (ADMs) to provide controlled access to such medications without the need for a pharmacist to personally fill every order. Certain ADMs are configured to provide access to only a single dose of a medication at a time. One way of accomplishing this is to provide a drawer having multiple fixed compartments where the distance that the drawer can be opened, and therefore the compartments that are exposed, is controlled by a processor.
In one method of use, a single dose of a medication is placed in one or more compartments of a drawer and the processor programmed with information including the type of medication placed in each compartment. When a caregiver requests a dose of this medication, the processor unlocks the drawer and allows the drawer to open until the first compartment of the drawer is exposed, whereupon the caregiver removes the medication from the first compartment and closes the drawer. When another caregiver requests a dose of the same medication, the processor unlocks the drawer and allows the drawer to open until the second compartment is exposed, as the processor previously recorded that the first compartment is now empty. The caregiver removes the dose from the second compartment and closes the drawer. This process is repeated with the processor allowing sequential access to the compartments of the drawer until all of the medications are removed.
Currently available drawers of this type control the distance that the sliding drawer is allowed to open using a solenoid-driven latch that is mounted within the sliding drawer to engage a ladder that is fixed to a drawer chassis that is mounted in the ADM. Such a system is disclosed in U.S. Pat. No. 5,716,114 to Holmes and Williamson and U.S. Pat. No. 6,109,774 to Holmes and Broadfield. The drawer-mounted solenoid is connected to the processor through a flexible electrical cable, such as a flat ribbon cable formed from multiple conductors laminated between layers of polyimide, between the sliding drawer and the fixed chassis, wherein the cable flexes each time the drawer is opened. These conventional drawers suffer from breakage of the ribbon cables over time as the constant flexing of the ribbon cables in the confined space induces sufficient stress between the polyimide layers that the ribbon cables eventually delaminate.